6G Celicas Forums

ok, im actually reading this emanage ultimate features stuff and looking to justify to upgrade over from my blue.

thn i spotted this feat called...

"A/T Shift Compensation Feature - On vehicles with Automatic Transmissions, ignition timing can be compensated at set shift-up and shift-down points".

and i remember i saw the abt the samething in HKS Fcon-Is

"Ignition Revision on an AT Vehicle···· Prone to knocking during shifting, this function remaps the ignition curve"

Does anyone know how does it work? Why is it on auto tranny, during shifting more prone to knocking?

The different load during gear shifts must be compensated for by adjusting the timing. The stock ECU handles this transparently but when you start messing with the signal using piggy backs you have to compensate for it manually.

Sudden change of load will make the engine more prone to knocking... You will actually get the same type of load change if you were to powershift a 5spd car with no lift-throttle shifting

Changing timing based on shifting is sort of a bandaid... On most standalone computers, there is an actual map you can tune for based on the rate of load change.